Roll crusher rebuilder



Aug. 29, 1967 K. G. CARTER 3,339,055

ROLL CRUSHER REBUILDER Filed June 2, 1966 5 Sheets-Sheet l INVENTOR.

KENNETH G.CA TER BY 6 flaw/(1U HIS ATTORNEY K. G. CARTER ROLL CRUSHER REBUILDER Aug. 29, 1967 5 Sheets-Sheet Filed June 2, 1966 FIG.4

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T N E M m o M INVENTOR. KENNETH G. CARTER v 2 immln [F l G. 5

BY (YA MM HIS ATTORNEY 1967 K. G. CARTER 3,339,055

ROLL: CRUSHER REBUILDER Filed June 2, 1966 5 Sheets-Sheet i I. ii!

INVENTOR. KENNETH G. RTER BY c// HIS ATTORNEY Aug. 29, 1967 K. G. CARTER ROLL CRUS HER REBUILDER Filed June 1966 5 Sheets-Sheet :5

fl'lllllllll' l l 724 "N2 222 2l8 734 730 SIB FIGJS INVENTOR. KENNETH G. CARTER CMWM H IS ATTORNEY 3,339,055 Patented Aug. 29, 1967 3,339,055 ROLL CRUSHER REBUILDER Kenneth G. Carter, 175 Virginia St., Salt Lake City, Utah 84103 Filed June 2, 1966 Ser. No. 554,739 17 Claims. (Cl. 219-76) This invention relates to a roll crusher rebuilding apparatus, and in particular, to an automatic roll crusher rebuilder which is mounted outboard from the crusher roll which is being rebuilt.

In recent years, roll crushers having smooth and/ or corrugated rolls have become very popular for crushing materials such as stone and minerals of various types. Such crushers generally comprise two rolls of the same diameter which are revolved towards each other at the same speed. One of the rolls is revolved about a fixed axis while the other revolves on a movable shaft. A nest of powerful springs generally holds the movable roll adjacent to the fixed roll or at a predetermined clearance and during a crushing operation the springs maintain a high pressure between the rolls to prevent materials from passing therethrough without being crushed. Most roll crushers are also provided with lateral adjusting means for shifting the rolls from side to side to minimize dishing or fianging of the surface of the rolls. However, the surface ultimately wears away as the crusher is used with the greatest wear taking place midway between the ends of said rolls, thereby forming a dish shaped roller surface. When this occurs, material which is to be crushed passes through said dished portion of the rollers without being subjected to the desired crushing action. Heretofore attempts have been made to fill in or rebuild the dished portion of the rolls without removing them from the crusher, by mounting a welding device directly above the rolls inside the crusher and thereby filling in said dished portion with welding metal. Such methods have proven to be unsatisfactory since the upper portion of the crusher often must be entirely removed before the rebuilding equipment can be placed over the rolls and inaddition, the close proximity of the welding equipment to the actual welding operation often damages said equipment. Additionally, rebuilding rolls in this fashion often means that the crusher must be shut down for a long period while the rolls are being rebuilt since a substantial portion of the rebuilding operation is manually controlled and operated.

It is accordingly a principal object of my invention to provide a roll crusher rebuilding apparatus which overcomes the disadvantages .and objections previously encountered in rebuilding crusher rolls.

An additional object of my invention is to provide a roll crusher rebuilder which is mounted outboard from the crusher rolls which are being rebuilt.

A further object of my invention is to provide an automatic roll crusher rebuilder.

A still further object of my invention is to provide a roll crusher rebuilding apparatus which uses tubular welding wire.

Still further objects of my invention will become apparent to those skilled in the art as the invention is better understood by reference to the detailed description appearing hereinafter.

According to my invention, the foregoing objects and at-' tendant advantages may be achieved by mounting a roll crusher rebuilding apparatus outboard from the crusher rolls which are to be rebuilt. The rebuilding apparatus is provided with tubular welding wire feeding means for feeding tubular Welding wire to the surface of the roll which is to be rebuilt wherein the wire is deposited ontothe surface of said roll by conventional welding techniques. The feeding means is adapted to coact with means for moving said tubular wire transversely across the face of the crusher roll to deposit the welding metal over the entire length of said roll. The rebuilder is also provided with turning means for rotating the crusher roll wherein the welding metal is deposited circumferentially around said roll, and in addition, said turning means enables said roll to be automatically shifted to new rebuilding positions during a transverse rebuilding operation. In a preferred embodiment of my invention, a plurality of rebuilding devices are mounted outboard from the crusher to simultaneously rebuild each crusher roll.

So that the invention may be more readily understood and carried into effect, reference is made to the accom-- panying drawing-s which are offered by way of example only and are not to be taken as limiting the invention, the scope of which is defined by the appended claims, which obviously embrace equivalent structures and processes.

FIGURE 1 is a perspective view of the rebuilder of my invention having a plurality of rebuilding means mounted outboard from a conventional roll crusher.

FIGURE 2 is a schematic wiring diagram of the components used in the roll crusher rebuilder.

FIGURE 3 is a perspective View of the preferred tubular wire feeding means and carriage means for moving said tubular wire across the face of the crusher roll.

FIGURE 4 is an enlarged plan view of the carriage drive means.

FIGURE 5 is a plan view of the preferred tubular wire feeding means.

FIGURE 6 is a sectional View of FIGURE 5 taken along line 66.

FIGURE 7 is a top view of the tubular wire feeding means shown in FIGURE 5.

FIGURE 8 is a sectional view of FIGURE 7 taken along line 8-8.

FIGURE 9 is a plan view of the nozzle and tip assembly for feeding tubular wire to the crusher roll.

FIGURE 10 shows the disassembled current pickup tip of FIGURE 9.

FIGURE 11 shows the switching means for reversing the direction of travel of the carriage shown in FIG- URES 3 and 4.

FIGURE 12 is a plan view of the ratchet relay used to control automatic speed changes and to initiate various operations of the rebuilding apparatus.

FIGURE 13 is a plan view of the rotary indexing and switching assembly.

FIGURE 14 is a schematic wiring diagram of the rotary indexing and switching assembly shown in FIG- URE 13.

FIGURE 15 is a plan view of the means of my invention.

Referring now more particularly to the drawings, FIG- URE 1 shows a perspective view of the roll crusher rebuilder of my invention mounted outboard from a conventional crusher 10 which is provided with a plurality of crusher rolls 12 and 14. Said rolls 12 and 14 are designed to revolve toward each other at the same speed, thus forcing material to be crushed between them. A plurality of the roll rebuilding devices of my invention are shown mounted outboard from crusher 10, i.e., essentially all of the components of the rebuilding apparatus are mounted away from rolls 12 and 14 which are to be rebuilt. Said rebuilding devices are mounted on frame 16 which substantially supports them at a position laterally away from an end of said roll. Tubular wire feeding means 18, hereinafter described, are. attached to carriage frames 20 which are slidably mounted on carriage bars 22. Carn'age drive means 24 propel carriage frames 20 back and forth along carriage bars 22 in a fashion hereinafter described. Tubular wire 26 is fed from spools 28 to feed ing means 18, which forces said wire 26 through nozzles preferred grounding 30 to current pick up tips 32, which are attached to the end of said nozzles 30. In operation, current passes from source 34, hereinafter described, along wire 36 to nozzles 30 wherein it passes along said nozzles 30 to tips 32. As tubular wire 26 passes through said tips 32, the current passes to the tips along said wire 26 to rolls 12 and 14 thereby causing said wire 26 to become molten and deposit on said rolls. Grounding cable conductor 38 is connected to rolls 12 and 14 through a special conducting contact which completes the circuit between said rolls and current source 34. Molten welding metal may be distributed transversely over the surface of rolls 12 and 14 by moving carriage frames 20 along carriage bars 22 while wire 26 is continually fed by tubular wire feeding means 18 to tips 32. Rolls 12 and 14 may also be circumferentially welded by rotating said rolls as wire 28 is fed to tips 32. This may be accomplished by drive means 40 which rotates sprocket 42. Said sprocket 42 is connected to sprocket 44, which is secured to roll 12, by drive chain 46. As hereinafter described, the rebuilding apparatus of my invention may be used in combination with circuitry which completely automates its action. As shown in FIGURE 1 and as previously described, a plurality of rebuilding devices may be used to deposit molten metal on each crusher roll at the same time. However, for simplicity in description, hereinafter, reference will be made to the use of a single rebuilding device with it being understood that a plurality of rebuilders can be used by duplicating the circuitry described, and this is preferred. In addition, it is understood that the rebuilding apparatus of my invention can be used to rebuild all types of surfaces and rolls even though the foregoing description refers only to crusher rolls.

FIGURE 2 shows a schematic wiring diagram of the rebuilding apparatus of my invention. In operating the apparatus, current is provided from a conventional source such as welding machine exciter 110 to power travel motor 122, the field of generator 150, and turn motor 204. To power travel motor 122, current passes along lines 112 and 114 to potentiometer 116, and thereafter, along line 118 to reversing switch 120 which controls the direction of said travel motor 122. As shown in FIGURE 2, reversing switch 120 is designed to enable current to flow through travel motor 122 in opposite directions by shifting said reversing switch 120 so that contacts on lines 118 and 126 complete a circuit with contacts on reversing switch 120 positioned along planes 123 and 124. Current passing through said travel motor 122 passes along line 126, through closed switch 128 in switching assembly 40 and along lines 130 and 132 back to exciter 110. Travel motor 122 can also be activated when switch 128 in switching assembly 40 is open by closing function switch 136. When this is done, current passes from motor 122, along lines 126 and 134 to said function switch 136. Thereafter said current passes along lines 138, 130 and 132 back to exciter 110.

Welding current is provided at tip 32 by passing a low amperage current from exciter 110 along lines 112 and 140 to electromagnetic field 142 of generator 150. The strength of said electromagnetic field 142 is controlled by potentiometer 146 which is connected thereto by line 144. Current passes through said potentiometer 146 along line 148 to line 132 and back to exciter 110. Electromagnetic field 142 activates generator 150 creating a welding current which flows along line 152 to potentiometer 154. Thereafter said current flows along line 156 to nozzle 30 and tip 32. When tubular wire 26 is passed through tip 32, current flows from said tip, along wire 26 to roll 12, thereby forming a molten pool of welding metal on said roll. Said current then flows to grounding means 158, along lines 160 and 162, and back to generator 150. It is to be noted that when tubular welding wire 26 is not moving through tip 32, current cannot pass between said tip and roll 12, Le, there is a gap between said tip 32 and roll 12 which is too large to maintain an arc therebetween, wherein further welding is prevented.

Tubular welding wire is fed through nozzle 30 and tip 32 by feed motor 184. As shown in FIGURE 2, said feed motor 184 is powered only when generator is operating and when relay 164 or function switch 178 is closed. When relay 164 is closed, current flows along lines 112 and 166 to coil 168, thereby closing magnetic switch 170. From thence, said current flows along line 172 to microswitch 174 which completes a circuit with said relay 164 when it is turned to a predetermined position, as hereinafter described. Said current then flows from relay 164 along lines 176 and 132 back to exciter 110. Relay 164 can be bypassed by closing function switch 178. When this is done, current flows along lines 172 and 180, through said function switch 178, and along line 182 to return line 132. As previously indicated, when current flows through coil 168, magnetic switch closes thereby allowing current to flow from generator 150 along line 152, through potentiometer 154, and along line 156 and 172 to feed motor 184. Thereafter, said current passes from said feed motor 184 along line 186 to potentiometer 188, which is used to control the speed of motor 184, and back to generator 150 along line 190, through closed switch 170, and finally along line 162 to generator 150.

Many of the functions of the rebuilding apparatus of my invention are controlled by rachet relay 164. Said relay 164 is activated by microswitches 192 which are in turn activated by the movement of push rod 194. Microswitches 194 allow a circuit to be completed, at predetermined intervals, between lines 200 and 202. When this is done, current flows along lines 112 and 196 to coil 198 which activates advancing paul 234 which in turn rotates relay 164. Current passes from coil 198 along line 200, through closed microswitches 192, and finally along line 202 to return line 132.

During the operation of my rebuilding apparatus it is necessary to periodically rotate roll 12. This is done by activating turn motor 204, which, as previously described, rotates sprocket 42 which drives sprocket 44, attached to roll 12, with chain 46. Turn motor 204 is activated by passing current along lines 112 and 206, through closed switch 208, and along line 210 to said motor 204. From thence, current passes along line 212 and line 132 back to eXciter 110'. Switch 208 is closed by passing current through coil 220. This may be done by closing function switch 214, closing microswitch 232 operated by relay 164, or closing locking switch 216. When function switch 214 is closed, current passes from line 112 along line 218 to said coil 220, thereby closing said switch 208. From coil 222, current passes along lines 222, 224, and 226 to function switch 214. From said function switch 214 said current passes along lines 228 and 230 to return line 132. Generally switch 208 is closed by completing a circuit through relay 164. To do this, current passes along line 222 to microswitch 232. When relay 164 is in a proper position, switch 232 closes and current passes therethrough along line 176 to return line 132. Locking switch 216 is designed to close when turn motor 204 begins to rotate and said switch 216 remains closed until roll 12 has rotated a predetermined distance. The function of switch 216 and its operation will be further described in greater detail.

As previously indicated, the rebuilding apparatus of my invention is designed to automatically deposit welding metal transversely and circumferentially on roll 12. In a transverse rebuilding operation, the rebuilding apparatus functions in the following fashion. Exciter 110 is activated which creates an electromagnetic field about generator 150, wherein said generator is rotated to produce a welding current. Travel motor 122 and feed motor 184 are powered wherein carriage 20 starts to move transversely in relation to roll 20 and tubular wire is fed through nozzle 30 to tip 32. When said tubular wire passes through tip 32 welding current passes from said tip to roll 12 thereby causing an are which melts said welding wire thereby depositing it on said roll 12. Since carriage 20 is moving in a transverse direction with relationship to roll 12, said welding metal is deposited along a transverse path on the surface of roll 12. As tip 32 approaches the end of roll 12, push rod 194 closes microswitch 192, which activates advancing paul 234 to rotate relay 164 to a position which prevents current from flowing to feed motor 184 by opening switch 170 thereby stopping said feed motor 184. When this occurs, welding current no longer passes between tip 32 and roll 12 since welding wire 26 is no longer passing through said tip whereby welding is discontinued at the ends of each pass. A second microswitch 192 is operated by the movement of push rod 192 which advances relay 164 during a predetermined number of transverse cycles, e.g., 1 to 6 cycles, thereby closing switch 208 to start turning motor 204 and slowing travel motor 122. Roll 12 is then rotated a predetermined distance at which time locking switch 216 automatically opens, in a fashion hereinafter described, thereby opening switch 208 which prevents current from flowing to turn motor 204. Once again travel motor 122 speeds up to a set speed for another first transverse pass of carriage 20* in a direction which is transverse to roll 12. However, said carriage 20 is now moving in a direction which is opposite from the direction in which it traveled during the previously described transverse weldng operation. The rotation of travel motor 22 is automatically reversed by reversing switch 120, which is activated by push rod 194 when tip 32 reaches a position proximate the edge of roll 12. As tip 32 begins to move back across roll 12 microswitch 192 is again closed thereby activating relay 164 to send current to feed motor 184. When this occurs, welding wire 26 begins to pass through nozzle 30 allowing current to flow between tip 32 and roll 12 wherein it is deposited in a second transverse path on said roll 12. This operation is repeated until transverse welds have been placed entirely around roll 12. In the preferred transverse welding method of my invention, relay 164 is programmed to allow tip 32 to make a plurality of passes over each transverse welding path before roll 12 is rotated. For example, relay 164 can be programmed to allow tip 32 to make from 1 to 6 passes along the same transverse path, and preferably 2 to 4 passes, before roll 12 is rotated. In this fashion, substantial amounts of metal can be deposited along each welding path which deposit has improved physical properties over a deposit of the same size made in one pass.

During a circumferential welding operation, generator 150 is activated to produce a welding current at tip 32. Roll 12 is then rotated while carriage 20 is held in a set position or advanced in small predetermined increments. In this fashion, a circumferential path of welding metal is formed around the surface of said roll 12. Travel motor 122 is activated by switch 128 to move tip 32 in small increments transversely over the surface of roll 12. Thus the rebuilding apparatus of my invention may be used to circumferentially wind welding metal of varying thicknesses over the entire surface of roll 12. This may be done by slowing the moving increments of carriage 20 while continually rotating turn motor 240 during a Welding operation. This may be done by adjusting potentiometer 116 which controls the speed of travel motor 122. A rebuilding operation of this type is made completely automatic by merely opening function switch 136 and closing switch 214 which allows travel motor 122 to advance a predetermined amount each time switch 128 operates, as hereinafter described, while turn motor 204 continues to operate.

The preferred carriage frame 20 and carriage bar 22 of my invention are shown in FIGURES 3 and 4. Carrier frame 20* is preferably slidably mounted on carrier bar 22 as shown in FIGURE 4. Rollers 312 are journaled to frame 20 to make said frame easily slidable thereon.

Travel motor 122 is secured to frame 20 by conventional attaching means and is positioned to drive two-speed sprocket 314 which coacts with chain 316'. As previously indicated, the speed of drive motor 122 is controlled by potentiometer 116, and, as shown in FIGURE 4, gear reduction box 318 may be used to further accomplish this purpose. Members 320 and 322 are attached to'opposite ends of bar 22 which are used to hold chain 316 in coacting relation with sprocket 314. Spring 324 is connected to one end of chain 316 with its opposite end being connected to mounting member 322. By connecting said spring 316 in this fashion, slack is automatically removed from chain 316 by spring tension, thus removing hesitation in carriage motion as the teeth on sprocket 314 coact with chain 316 to propel carriage frame 20' on bar 22. This provides a safety feature in that it prevents breakage of the drive in case of malfunction or obstruction of carriage 20', and in addition, chain 316 may be disengaged from two-speed sprocket 314 by merely lifting it upwardly and away from said sprocket 314. Adjustable carriage stops 326 are slidably mounted on bar 22 on either side of carriage frame 20', and are adapted with outwardly extending members which coact with push rods 194 and 195. Said carriage stops 326 may be set to any location on carriage bar 22 by loosening and resetting screws 328.

Tubular wire feeding means 18, hereinafter described, is secured to carriage frame 20 as shown in FIGURE 3. Nozzle 30 is connected to said tubular wire feeding means 18 so that tubular Wire fed by' said feeding means 18 passes into the center of said nozzle 30 and exits therefrom through current pickup tip 32. Support 330 is secured to the end of carriage bar 22 to provide a guide and a support for nozzle 30' as it is propelled back and forth by carriage 20. Support 330 also holds nozzle 30 in a proper position with respect to roll 12 during a rebuilding operation.

The development of tubular welding wire in recent years has provided the means for hardfacing crusher rolls with high alloy metal by a semi and fully automatic process such as described herein. Tubular wire is made from metal tape in a fashion very similar to the method one would use to construct a handmade cigarette. Such tubular wires have several inherent faults. The principal purpose of tubular wire feeding means 18 is to overcome these faults. For example, even when the wire has been finish drawn to size, heat treated, layer wound and packaged, it exhibits a twisting tendency when it is uncoiled. This tendency makes feeding the wire through the necessary tubes, guides, nozzles and current pickup tips, hereinafter described, most difficult. In addition, the tubular wire is very sensitive to various types of deformation. The most common type is flattening of the wire which often prevents it from being properly fed to the roll which is being rebuilt. In addition, the surface of the wire is often marred which results in poor current pickup.

FIGURES 5 to 8 illustrate the preferred tubular wire feeding means 18 of my invention. FIGURE 5 shows a plan view of the feeding means which clearly illustrates the relationship between the drive gears and their coaction with each other. As shown, three sets of drive gears, i.c., drive gears 350 and 352, drive gears 354 tnd 356, and drive gears 358 and 360, are mounted to coact with each other. Synchronizing gears 362 and 364 are each mounted to coact with two pairs of drive gears to synchronize the movement of any one pair of drive gears with the movement of the other pairs. In this fashion, all of the drive gears are moving at the same speed as any one drive gear. In addition, the gears are positioned so that all of them are rotated when any one gear is rotated. For example, if synchronizing gear 362 is rotated in a clockwise direction, it coacts with gears 352 and 356 to drive them in a counterclockwise direction. In turn, drive gear 352 coacts with drive gear 350 and drive gear 356 coacts with drive gear 354 to drive said gears 350 and 354 in a clockwise direction. In addition, drive gear 356 coacts with synchronizing gear 364 to rotate said gear in a clockwise direction. As shown, synchronizing gear 364 coacts with drive gear 360 to drive said gear in a counterclockwise direction and drive gear 360 coacts with gear 358 to drive said gear in a clockwise direction.

Drive gears 350, 354 and 358 are mounted on slide blocks 366, 368 and 37 0 respectively. All other drive gears and synchronizing gears are mounted on main mounting blocks 372. As shown in FIGURES 6 and 7 grooved rolls are attached to each of the drive gears, i.e., grooved roll 374 is attached to drive gear 350, grooved roll 376 is attached to drive gear 352, grooved roll 392 is attached to drive gear 354, grooved roll 394 is attached to drive gear 358, etc. Each grooved roll is provided with groove 378 about its entire top surface which is adapted to coact with wire 26. While grove 378 may have any shape with a plurality of driving points which coact with wire 26, I prefer to use a groove having two smooth and substantially plane sidewalls which contact each other at an angle of about 100 to 30 and most preferably about 60 to 35, shown as angle A in FIGURE 6. By using a smooth angular groove of this type certain advantages are obtained. For example, such a groove will not cause the seam in the tubular wire to open and in addition will prevent marring of the surface of the wire which can result in its breakage.

Drive gears 350, 354, and 358 are rotatably mounted on slide blocks 366, 368 and 370 respectively by journaling said drive gears thereto with conventional journaling means such as bolts 380 which passes through said drive gears and grooved rolls and which are screwed into the slide blocks 366, 368 and 370. Similarly, drive gears 352, 356 and 360, and synchronizing gear 364 are journaled to main mounting block 372. Ball bearings 384 may be positioned between said drive gears and bolts 380 and between said grooved rolls and bolts 380 to insure easy rotation of said drive gears and rolls on said bolts. Synchronizing gear 362 is also rotatably mounted on main mounting block 372 but said gear is connected to drive shaft 385 which coacts with feed motor 184. The grooved rolls and drive gears are attached to each other by the use of conventional bolts 382 which pass through said drive gears and are screwed into said grooved rolls.

Slide blocks 366, 368 and 370 are attached to main mounting block 372 with bolts 386 which passes through said slide blocks and are screwed into threads 384 formed in main mounting block 372, as shown in FIGURE 8. Springs 388 are positioned between the head of bolts 386 and inwardly extending ledge 389 positioned inside said slide blocks 366, 368 and 370. In this fashion, said slide blocks are forced towards main mounting block 372. Cap 390 is placed in the port above bolt 386 to prevent dirt and other undesirable materials from falling into contact with spring 388, thus preventing its etfective operation.

By using a tubular wire feeding means of the type previously described, several advantages are obtained. For example, each pair of drive rolls contacts tubular wire 26 without requiring excessive pressure to be exerted between any single pair of grooved rolls. In addition, the dual drive provided between each pair of rolls provides additional drive power. As a result, a reduced pressure on wire 26 is required to continuously drive it through nozzle 30 and tip 32. The tubular wire driving means herein described also acts as a wire straightener since the tubular wire must pass through three separate sets of driving rolls in line with each other.

The tubular wire feeding means of my invention is generally provided with an inlet guide, not shown in the drawings, which directs tubular wire 26 between the first pair of drive rolls attached to drive gears 350 and 352. A second guide, i.e., an outlet guide 410 as shown in FIG- URE 9, generally provided between the drive rolls at;

tached to drive gears 358 and 360 to direct tubular wire which has passed through feeding means 18'into nozzle 30.

Nozzle 30 with current pickup tip assembly 32 is shown in detail in FIGURES 9 and 10. Outlet guide 410 is atattched to one end of nozzle 30 and as previously indicated, said guide 410 is adapted to direct tubular welding wire from feeding means 18 into the center of said nozzle 30. The other end of nozzle 30 is provided with current pickup tip means 32 which comprise the components within the broken lines shown in FIGURE 9 and which are shown in detail in FIGURE 10. Adjustable clamp 412 and insulated mounting assembly 414 are attached to nozzle 30 and are positioned to slidably coact with slide rod 416 which is attached to crusher 10 at a position above roll 12 and which may be fixedly attached at one end to support 330 which is in turn attached to carriage bar 22. When the rebuilding device of my invention is in operation, nozzle 30 slides along a predetermined path determined by the position of slide rod 416, and in this fashion, tip assembly 32 moves over an unchanging path during an entire rebuilding operation.

The components which make up current pickup tip assembly 32 are shown in detail in FIGURE 10 as previously indicated. Spring liner 420 passes through the entire length of nozzle 30 and is connected at one end to outlet guide 410 and at its other end to nozzle tip 422. Centering sleeve 424 is positioned over spring liner 420 to maintain said spring liner in the approximate center portion of nozzle 30. Tip nut 426 slides over the end portion of nozzle tip 422 and is thereafter screwed to the end of nozzle 30 to securely hold tip 422 in a welding position on said nozzle 30. As shown in FIGURE 9, tubular welding wire passes through tip 422 to form an electrical arc contact with the crusher roll which is being rebuilt.

FIGURE 11 illustrates one of the preferred carriage reversing and impulse switches of my invention. Push rods 194 and 195 are slida'bly mounted through slides 512 which are attached to switch base 510. Said switch base 510 is secured to carriage frame 20. As carriage frame 20 moves along carriage bar 22, push rods 194 and 195 contact travel stop 326 thereby pushing said push rods into contact with rnicroswitches 192. As shown in FIGURE 11, push rods 194 and 195 are connected by spring 514. Accordingly, when push rod 194 is moved to operate microswitches 193, push rod 195 is pulled into an operative position so-that when carriage frame 20 moves in the opposite direction, said push rod 195 will be in an operative position with microswitch 192.

FIGURE 12 shows the preferred relay 164 of my invention. In operation, current passes along line 196 through coil 198 and along line 200 to activate advancing paul 234. When this occurs, said paul 234 coacts with rachet teeth 612 on relay 164, thereby rotating said relay about shafit 165. Indexing switch 610, which represents switches 174 and 232 in FIGURE 2, rides on a portion of said relay 164 to contact circuit means 614 which forms a circuit between line 176 and switch 610. When current is not passing through coil 198, spring 616 pulls racheting pauls 234 outwardly away from teeth 612 of relay 164 wherein said racheting paul 234 is positioned to rotate relay 164 once again when current is passed through said coil 198. Said spring 616 is fixedly attached between one end of racheting paul 234 and support means 618.

Roll turning means 40 is shown in detail in FIGURES 13 and 14. Said turning means is mounted in support frame 710 which is provided with center support member 712 for supporting components of said turning means. Turning means 40 consists of driving means and switching assembly for controlling said driving means. The major components of said switching assembly are large disc 714 and indexing wheel 7-16. Said large disc 714 is attached to shaft 718 which is in turn journaled to frame 710. Reduction gear 720 is also attached to shaft 718 and is used to drive said large disc 712 at a predetermined speed. Said reduction gear 720 is driven by drive gear 722, which is secured to drive'shaft 724 which is in turn driven by turn motor 204 as shown in FIGURE 2. Drive gear 722 and reduction gear 720 are selected to turn large disc 714 at approximately the same speed as the surface of the crusher roll which is to be rebuilt. Index wheel 716 is provided with outer rim 728 which forms a friction contact with large disc 714 when said indexing wheel 716 is forced against said large disc 714. Said indexing wheel 716 is journaled to support member 730 by shaft means 732. Said support 730 is in turn pivotally mounted to frame 710 by pivot means 734. When current passes through coil 220, indexing wheel 716 is forced against the approximate outside edge of large disc 714 wherein said indexing wheel 716 rotates when large disc 714 turns. When current is not passing through coil 220, spring 738 pulls indexing wheel 7 1 6 away from large disc 714 so that said large disc 714 may rotate without turning said indexing wheel 716.

In operation, relay 164 is rotated to complete a circuit between lines 218 and 222, thereby current passes through coil 220. When this occurs, as previously indicated, indexing wheel 716 is forced against the side of large disc 714. In addition, switch 208 is closed which allows current to flow to motor 204, whereby large disc 714 is rotated (rotated at the same approximate speed as the crusher roll being rebuilt). Indexing wheel 716 also rotates as this occurs, and microswitch 216 moves out of notch 740 placed on the edge of said indexing wheel 716 thereby locking switch 208 so that motor 204 will continue to rotate even though relay 164 moves to a new position which will not allow current to flow between lines 222 and 132. When indexing wheel 716 has rotated one complete revolution, microswitch 216 is again opened as said switch moves into notch 740, thereby preventing current from flowing through coil 2'20 and thus to motor 204. During a transverse welding operation, crusher roll 12 must be turned a suflicient distance between each welding pass to provide for proper heat distribution. This can be controlled by the size of indexing wheel 716 and large disc 714. In the preferred embodiment of my invention, indexing wheel 716 has a circumference of between about 3 and 8 inches whereby the surface of the crusher roll being rebuilt will be rotated between 2 and 12 inches for each rebuilding path depending on the drive ratio selected.

During a circumferential welding operation, tip 32 is preferably moved transversely a predetermined distance for each revolution or round of the weld bead. I have found that if this move is made in several small increments while the crusher roll is rotated several advantages exist. For example, no attention need be given to the size of the roll being welded nor is it important that the nozzle be moved at a definite place on the roll. To accomplish this purpose, notch 742 is placed on the outer circumference of large disc 714. Microswitch 128 rides on the surface of said large disc 714 and coacts with said notch 742 during each revolution of said disc 714. When this occurs, microswitch 128 is closed for a short period thereby allowing current to pass through travel motor 122, and thus moving tip 32 in a transverse direction over roll 12. The overall distance of the tip movement can be controlled by the speed of travel motor 122 which is in turn controlled by potentiometer 116.

As previously indicated, the flow of welding current is from current pickup tip 32 through welding wire 26 to roll 12 and then back to the source of welding current along line 38. Line 38 must be securely contacting roll 12 so that the welding circuit will not be broken during a welding operation. FIGURE 15 illustrates the preferred method of my invention for grounding said line 38 to roll 12. As shown, grounding shoe 810 is journaled to crusher frame 812 by shaft 814 and is insulated from its mounting to prevent welding current from flowing through the crusher bearings. Said grounding shoe 810 is positioned substantially adjacent to the end of roll 12 so that it can be rotated into contact therewith during a rebuilding operation. Said grounding shoe 810 is held securely against said rolls end by spring 816 which is attached to crusher frame 818. Grounding shoe 810 of my invention performs two functions. Firstly, it provides a ground between roll 12 and line 38 thereby completing the welding circuit, and in addition, grounding shoe 810 provides a means for breaking the rotation of roll 12 so that it does not over rotate during a rebuilding operation.

As indicated, the rebuilding apparatus of my invention is mounted outboard from the crusher rolls which are being rebuilt. The outboard mount becomes very important during a rebuilding operation since it allows the wire feeding and travel components to be mounted out of the area of weld splatter, smoke and damaging dirt. In addition, it allows said feeding and travel components to be mounted where they can be constantly observed for proper function and operation. To accomplish this purpose carriage bar 22 is mounted on frame 16 which provides a stationary platform for said carriage bar 22. As previously indicated, carriage bar 22 in turn supports feeding means 18 and carriage 20. Frame 16 is preferably supported by adjustable legs which can be lengthened or shortened to properly position the rebuilding apparatus of my invention outboard from the crusher rolls which are to be rebuilt. It will be understood throughout that the term outboard refers to the method of mounting feeding means 18 and carriage 20 laterally away from the crusher rolls which are being rebuilt, i.e., moved to a position that is away from the vertical plane above said rolls. It is, of course, understood that at least a portion of nozzle 30 and tip 32 must be positioned within said vertical plane above the crusher rolls. Also, while it is preferred to mount frame 16 on members not connected to crusher 10, the term outboard mounting refers only to the position or location of said feeding means 18 and carriage 20, not to the method of securing said feeding means and carriage out-board from said crusher 10.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects, and therefore, the purpose of the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. Apparatus for rebuilding the surface of a metal roll, which roll is rotatably mounted to turn about its center axis, comprising a mounting frame positioned laterally away from an end of said metal roll; carriage means mounted on said mounting frame adapted to move on said mounting frame in a direction substantially parallel with the center axis of said roll; feeding means connected to said carriage means for feeding tubular welding wire; nozzle means, for passing said tubular welding wire from said feeding means to said roll, having a first end and a tip end wherein said first end is attached to said carriage means in a position laterally away from an end of said roll in coacting relationship with said feeding means for receiving welding wire and passing said wire to said tip end of said nozzle which is positioned in welding relationship with said roll; and welding means attached to said nozzle means for passing welding current between said tip end of said nozzle and said roll when tubular welding wire passes through said tip end wherein molten welding wire is transversely deposited on said roll when said carriage means moves on said mounting frame.

2. The apparatus of claim 1 wherein said carriage means is provided with drive means for propelling said carriage means on said mounting frame in a direction substantially parallel with the center axis of said roll.

3. The apparatus of claim 2 wherein said drive means for propelling said carriage means is provided with automatic reversing means for reversing the direction of travel of said carriage means on said mounting frame when said tip end of said nozzle means is at a point proximate a lateral edge of said roll.

4. The apparatus of claim 1 wherein turning means are attached to said roll for rotating said roll about its center axis.

5. The apparatus of claim 4 wherein said turning means is provided with control means for activating said turning means at predetermined intervals.

6. The apparatus of claim 5 wherein said control means is programmed to activate said turning means when said tip end of said nozzle means is at a point proximate a lateral edge of said roll.

7. The apparatus of claim 1 wherein said feeding means comprises a plurality of pairs of rotatably mounted grooved rolls positioned in line with each other for passing tubular welding wire between each pair and wherein each of the grooved rolls are provided with drive means for rotating each of said rolls at the same speed.

8. The apparatus of claim 7 wherein each pair of said grooved rolls is provided with biasing means for urging said rolls together.

9. The apparatus of claim 8 wherein said feeding means contains three pairs of rotatably mounted grooved rolls.

10. The apparatus of claim 9 wherein each of said grooved rolls are provided with a groove having two substantially plane sidewalls which sidewalls contact each other at an angle of 30 to 100 degrees.

11. The apparatus of claim 2 wherein said carriage means is a carrier frame slidably mounted on a carrier bar and said drive means for said carriage means comprises motor driven sprocket means rotatably mounted to said carrier frame and chain means attached to opposite ends of said carrier bar under spring tension in coacting relationship with said sprocket means wherein said sprocket means moves along said chain means as said sprocket means rotates, said chain means being adapted to be lifted away from and disengaged from said sprocket means.

12. The apparatus of claim 2 wherein said feeding mean-s is provided with switching means for deactivating said feeding means when said tip end of said nozzle reaches the end of a pass over the surface of said roll during a transverse rebuilding operation to prevent welding at the end of said pass.

13. The apparatus of claim 4 wherein said feeding means is provided with switching means-for deactivating said feeding means when said tip end of said nozzle reaches the end of a pass over the surface of said roll during a transverse rebuilding operation to prevent welding when said roll is rotated to a position for another transverse pass.

14. Apparatus for rebuilding the surface of a metal roll, which roll is rotatably mounted to turn about its center axis, comprising a mounting frame positioned laterally away from an end of said roll; feeding means attached to said mounting means for feeding tubular welding wire; nozzle means, for passing said tubular welding wire from said feeding means to said roll, having a first end and a tip end attached to said feeding means in a position laterally away from an end of said roll and a tip end positioned in welding relationship with said roll; welding means attached to said nozzle means for passing welding current between said tip end of said nozzle and said roll when welding metal is passed through said tip end, and turning means attached to said roll for ro tating said roll about its center axis wherein molten weld ing metal wire is circumferentially deposited on the surface of said roll as it rotates.

15. The apparatus of claim 14 wherein said nozzle means is laterally movable in a direction substantially parallel with the center axis of said roll.

16. The apparatus of claim 15 wherein said nozzle means is provided with carriage means programmed to move said nozzle means a predetermined distance at predetermined intervals.

17. The apparatus of claim 16 means is programmed to move said nozzle each complete revolution of said roll.

wherein said carriage means after References Cited UNITED STATES PATENTS RICHARD M. WOOD, Primary Examiner. 

1. APPARATUS FOR REBUILDING THE SURFACE OF A METAL ROLL, WHICH ROLL IS ROTATABLY MOUNTED TO TURN ABOUT ITS CENTER AXIS, COMPRISING A MOUNTING FRAME POSITIONED LATERALLY AWAY FROM AN END OF SAID METAL ROLL: CARRIAGE MEANS MOUNTED ON SAID MOUNTING FRAME ADAPTED TO MOVE ON SAID MOUNTING FRAME IN A DIRECTION SUBSTANTIALLY PARALLEL WITH THE CENTER AXIS OF SAID ROLL; FEEDING MEANS CONNECTED TO SAID CARRIAGE MEANS FOR FEEDING TUBULAR WELDING WIRE; NOZZLE MEANS, FOR PASSING SAID TUBULAR WELDING WIRE FROM SAID FEEDING MEANS TO SAID ROLL, HAVING A FIRST END AND A TIP END WHEREIN SAID FIRST END IS ATTACHED TO SAID CARRIAGE MEANS IN A POSITION LATERALLY AWAY FROM AN END OF SAID ROLL IN COACTING RELATIONSHIP WITH SAID FEEDING MEANS FOR RECEIVING WELDING WIRE AND PASSING SAID WIRE TO SAID TIP END OF SAID NOZZLE WHICH IS POSITIONED IN WELDING RELATIONSHIP WITH SAID ROLL; AND WELDING MEANS ATTACHED TO SAID NOZZLE MEANS FOR PASSING WELDING CURRENT BETWEEN SAID TIP END OF SAID NOZZLE AND SAID ROLL WHEN TUBULAR WELDING WIRE PASSES THROUGH SAID TIP END WHEREIN MOLTEN WELDING WIRE IS TRANSVERSELY DEPOSITED ON SAID ROLL WHEN SAID CARRIAGE MEANS MOVES ON SAID MOUNTING FRAME. 